People with Alzheimer's disease who develop infections such as chest, intestine and urinary-tract infections may suffer double the rate of memory loss. Researchers from Southampton University studied 222 older people with Alzheimer's disease. Between them 110 of the 222 participants had had a severe infection and those participants who had had one or more infection over the course of the study showed twice the rate of cognitive decline. The infections can lead to a high level of a protein called Tumour Necrosis Factor (TNF) in the blood, a protein which has been linked to inflammation. Inflammation is, in turn, though to contribute towards dementia.
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